Topband
[Top] [All Lists]

Re: Topband: Homebrew capacitors

To: topband@contesting.com
Subject: Re: Topband: Homebrew capacitors
From: Bill Cromwell <wrcromwell@gmail.com>
Date: Sun, 29 Sep 2013 20:19:14 -0400
List-post: <topband@contesting.com">mailto:topband@contesting.com>
Hi Jim,

When I used it I connected the center conductor at one end and the braid at the other end. The bit that I used for the small coupling capacitance was not very long. Even the short length I used kept the output of one circuit further away from the input of the other circuit.

Some antenna circuits use them by connecting one leg of the antenna to the center conductor and the shield at the same end to the next leg of the antenna. I believe I am thinking of a trap that was tuned this way. The coax was the resonating capacitance for the trap and the open end could be trimmed to resonance, sealed against the weather and then - rolled up conveniently. I did not build that circuit but have kept it in mind as a possibility. It probably depends more on what is convenient.

73,

Bill  KU8H


On 09/29/2013 07:42 PM, Jim GM wrote:
Could have saved more money with a Piece of RF-9913 or RG8 coax cable about
25pF per foot plenty voltage rating.


Only thing can some one please help me on this, do I connect the center
conductor on one end of the cable and use the shield on the other end? Or
just use the  center conductor and shield on one end, while the other end
are floating not used and not tied together?
Diagram below 0= connection point.

      ________________________________0

      ________________________________0

OR

      0________________________________
       _________________________________0


Jim K9TF


_________________
Topband Reflector

<Prev in Thread] Current Thread [Next in Thread>